The chest, made by a company that has recalled millions of hope chests for safety reasons, had a design flaw that meant that it could not be opened from the inside, leaving 7-year-old Sean Munroe and his 8-year-old sister Lexi to suffocate, law enforcement officials said.

Their father, Sean Munroe, was apparently watching football and had no idea the children were in distress, according to Eric Munroe, his brother. Another television set was on in the boy’s room. Their mother, Gillian Munroe, was not home.

As investigators unraveled the details of the tragedy Monday, friends and family spoke of a devoted, hard-working family and children known for their easy smiles and playful nature.

“They’re a wreck right now,” Munroe said of the two grieving parents, noting in a telephone interview that his brother had found the children in the chest and called 911. “These were the most wonderful, loving children.”

Norfolk District Attorney Michael Morrissey said the chest was made by Lane Furniture of Virginia, but that investigators had yet to identify the model or when the chest was made. He said the family had bought it used about 12 years ago.

“It has some type of locking mechanism that did not have the ability to be unlocked from the inside,’’ he said.

In 1996, Lane Furniture recalled 12 million chests with lids that automatically latched shut when closed. The recall followed reports of at least six children suffocating in the chests. The recall sought all Lane and Virginia Maid brand cedar chests made between 1912 and 1987. The company offered to provide new locks free of charge to prevent entrapment, federal regulators said.

It was unclear Monday if the hope chest involved in the deaths of the two children was among the models recalled.

In 2001, the US Consumer Product Safety Commission issued a $900,000 fine against Lane for failing to report the entrapment problem in a timely manner. It was the third-highest fine the agency assessed that year.

“This was a significant penalty for the agency,” said Scott Wolfson, a spokesman for the agency, noting that companies are obliged under federal law to report immediately any safety failures of consumer products. “They failed to do that,” he said.

In the aftermath of the recall, Lane made a concerted effort to educate its customers about the hazards and the recall, traveling around the country to offer free fixes. But that was not enough to stop at least one additional death and two near suffocations after 2000, according to the agency.

A hope chest is typically a large, sometimes ornamental wooden box used for storage. The name harkens to a time when women would accumulate clothes, linens, and other items in anticipation of being married.

Officials at Lane, a century-old company acquired by Heritage Home Groups of St. Louis, did not return calls for comment Monday.

RECALL NOTICE AND PHOTO POSTED BY THE US CONSUMER PRODUCT SAFETY COMMISSION, 2006: The Lane Co., of Altavista, Va., is calling for a renewed search for cedar chests to replace their locks. In 1996, Lane recalled 12 million chests with lids that automatically latch shut when closed, following reports of six children suffocating. . . . All “Lane” and “Virginia Maid” brand cedar chests manufactured between 1912 and 1987 need to have their locks replaced. The chests are often handed down through families, and it is likely that many were purchased second-hand. [Photo does not represent the chest in which the Munroe children perished.]

Recounting the early details of the investigation into the deaths in Franklin, Morrissey said that all the children in the Munroe family and at least one parent gathered for dinner around 6 p.m. Sunday. “We are trying to sort out events that occurred after that,’’ he said.

The children were discovered in the chest around 8 p.m., both unresponsive. They were taken to hospitals in Norwood and Milford, where they were pronounced dead. Morrissey said autopsies by the state medical examiner’s office are scheduled for Tuesday.

Morrissey said no decision can be made about how to treat the incident legally until the autopsies are completed.

“It was difficult for investigators to speak with family members last night [because] they were going through a very painful period,” he said. “The investigation is continuing.”

He added: “Any time you lose a child, it’s tragic. To lose two, it’s horrific.”

Cayenne Isaksen, spokeswoman for the state Department of Children and Families, said, “The department has received a report related to the incident and is investigating. We do not comment as to whether or not a family has a prior history with the department.”

At the Davis Thayer Elementary School in Franklin, which the children attended, school officials called in grief counselors Monday to console students, parents, and staff.

Sean, the youngest of the family’s five children, was known to favor mohawks, loved fishing and playing with his pet chickens and bunnies, and was regarded as uncommonly resilient, often continuing to play after scraping his knees or falling in the mud.

Friends, relatives, and school officials said his sister often helped other students in her third-grade class with homework, liked to paint her nails with sparkles, and had the kind of wide, angelic smile that made friends want to hug her and come over to play with her favorite dolls.

JESSICA RINALDI FOR THE GLOBE

The Munroe family home on Chestnut Street in Franklin.

“The kids were both lovely, lovely children . . . bright, energetic, heavily involved in the school community,” said Maureen Sabolinski, superintendent of Franklin Public Schools. “They were from a nice, really engaged family. They were really part of the fabric of the school community.”

She described their school, with only 335 students between kindergarten and fifth grade, as tightly woven. “This is a very deep, profound loss for us,” she said.

Friends of the Munroes described the parents — the father sweeps chimneys for a living and the mother works at Home Depot — as
devoted to their children. “Everything they did they did for their children,” said Andree Grover, a friend from Franklin. “They’re just a beautiful family. It’s devastating.”

Her daughter, Shay Grover, is close friends with the Munroe’s eldest daughter, who is 15 and has often visited their home. She said in a phone interview that Lexi always greeted her at the door with a big smile, with Sean, the only boy in the family, usually right behind, also with a bright smile.

“They loved people coming over and spending time with them,” she said.

When Shay Grover spoke with her friend on Monday, she told her the family was struggling. “They’re in shock,” she said. “They’re all trying to stay strong.”

On Monday, friends and neighbors came to the family’s house and left platters of food, flowers, and a white teddy bear. The family’s landlord, Joe Proia, called the Munroes a “great, hard-working family.”

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